The main disadvantage of direct observation method is: MCQ with Answer and Explanation

Explanation:
It is always logically true that the number possessing A cannot be less than those possessing both A and B, and it is required for consistency.

Explanation:
The product should equal the value ratio Σp₁q₁/Σp₀q₀, i.e., the value index.

Explanation:
CPI measures average price changes paid by consumers for a basket of goods and services, directly indicating inflation's impact on household purchasing power and cost of living.